1. Field of the Invention
This invention relates in general to a dental floss device, and in particular to a self-contained and reusable dental floss device that is easy to operate and inexpensive to manufacture.
2. Prior Art
Flossing teeth regularly has long been recommended by dentists and is practiced by many people around the world. The conventional way of flossing is wrapping the free ends of a strand of dental floss around middle fingers of each hand. The floss section between the fingers is kept tensioned and guided by index fingers and thumbs and then passed successively between tooth pairs. The tensioning makes it necessary for the floss to be wrapped around middle fingers very tightly to prevent the floss from slipping. In addition, fresh floss has to be fed from one of the fingers to replace soiled/frayed section which in turn is wound onto the other finger. Anyone who has flossed knows that tightly wrapped fingers are not very comfortable. Often times the wrapped fingers turn to purple and feel numb due to lack of blood flow. Further, one of the holding fingers is wrapped by spent floss which is wet and soiled causing additional discomfort for the user.
Dental floss devices/holders/applicators have been invented in attempt to make dental flossing easier and less painful. A search revealed numerous United States Patents issued concerning dental flossing devices/holders/applicators. The following US Patents are believed to be more closely related to the current invention:
______________________________________ 553,610 4,051,857 5,056,540 1,306,998 4,094,328 5,060,681 1,640,607 4,460,002 5,067,503 2,187,442 4,706,694 5,069,233 3,746,017 4,790,336 5,105,840 3,927,687 4,807,651 5,125,424 ______________________________________
All the dental floss devices described in the prior art, regardless of their appearance and complexity in structure, include a handle and a floss head where a tensioned string member is held. Users of these devices floss by holding on to the handle and extending the floss head into the mouth and passing the tensioned string member between tooth pairs. Most of these devices have the floss head fixed in position. Others such as The Dimitroff U.S. Pat. No. 1,306,998, The Ray U.S. Pat. No. 4,094,328 and The Lamber U.S. Pat. No. 4,706,694 offer some limited degree of flexibility by allowing the floss head to rotate relative to the handle. However, teeth are oriented in various directions and complex ways. Some of them like front ones are straight forward while those in the back are often hard and awkward to reach. Proper and effective flossing requires complex manipulation of floss including continuous change in direction, tension and motion of floss string between tooth pairs and around teeth inside mouth. Such maneuvering is not an easy chore for even highly flexible human hands and certainly a very difficult task for floss devices with no or limited flexibility. Therefore, whatever the merits, features and advantages of the devices disclosed in the prior art, none of them can provide as adequate means for proper and effective flossing as human hands can.
In addition, in considering their structure and functioning, all the devices described in the prior art can be categorized as disposable and reusable. Devices of the disposable type are usually simple in structure and inexpensive to use. However, one such device can hardly last long. Once the tensioned string member becomes frayed, it can no longer be used effectively. As a result, a user usually needs several of these disposable devices to complete full mouth flossing. As inexpensive as these devices may seem, the accumulated cost can still be substantial. And so is the impact on environment as these devices are usually made of non-degradable materials such as plastic. On the other hand, the devices of the reusable type usually last long time with only floss cartridges needed to be replaced intermittently. Nevertheless, they are inherently much more complicated in structure--providing tension and dispensing of floss are accomplished by mechanical means involving many parts which increase the complexity of the devices as well as the cost to manufacture and to use.
The dental floss device disclosed in the current invention takes full advantage of the flexibility and maneuverability of human hands as well as the habit of flossing with bare hands which millions of people have developed. Among other features and advantages, the most distinctive feature of the dental floss device disclosed in the current invention is that the device relieves fingers from being wrapped tightly and being in contact with wet and soiled spent floss while flossing with the device is very much the same as flossing with bare hands. Moreover, this device is self-contained, reusable and is easier and less expensive to manufacture.